Electric vehicle driving mode control method and device

Abstract

The present disclosure provides an electric vehicle driving mode control method and device, the method comprising: calculating the current road adhesion coefficient and road traffic coefficient, obtaining the safety control upper limit value, the safety control lower limit value and the safety control output value; obtaining the current in-vehicle passenger information, obtaining the comfort control upper limit value and the comfort control output value; collecting the driving parameters of the vehicle in the driving state, matching the driver's expected level with the actual level of the vehicle, and obtaining the driver's expected coefficient; and obtaining the driving mode control output result after calculation based on the driver's expected coefficient, the comfort control output value, the comfort control upper limit value and the safety control lower limit value. The electric vehicle driving mode control method and device provided by the present disclosure take into account driving safety, riding comfort and meet the differentiated needs of drivers, realize real-time adjustment and automatic control of driving modes, meet different driving needs in complex environments, reduce driving intensity, and improve vehicle safety.

Description

Technical Field

[0001] The present disclosure relates to the technical field of electric vehicles, and in particular to a method and device for controlling a driving mode of an electric vehicle. Background Art

[0002] Due to the driving characteristics of the motor, most electric vehicles do not have different driving modes for drivers to choose from. Drivers cannot choose different driving modes according to their preferences or different road conditions to make the vehicle's power response more in line with their expectations, resulting in a poor driving experience.

[0003] Currently, the vehicle driving mode and the differences between different driving modes are calibrated by vehicle engineers. The driver needs to manually select the driving mode, and the selectable driving modes are limited. The driver can only choose one of the driving modes preset by the engineers in the vehicle during driving. The vehicle responds to the driver's throttle operation, that is, executes the matched data in the program. The selectable driving modes are limited and the flexibility is poor. Too few driving modes preset by vehicle engineers cannot meet the diverse needs of drivers, and too many preset driving modes will make the system cumbersome and unable to take into account the needs of economy. Summary of the invention

[0004] The purpose of the present disclosure is to provide an electric vehicle driving mode control method and device, which can solve one or more of the above-mentioned prior art problems.

[0005] According to one aspect of the present disclosure, a method for controlling a driving mode of an electric vehicle is provided, comprising:

[0006] Calculate the current road adhesion coefficient and road traffic coefficient, and combine them with the initial control value to obtain the safety control upper limit value, safety control lower limit value and safety control output value;

[0007] Obtain the current passenger information in the vehicle, and obtain the comfort control upper limit value and the comfort control output value by combining the safety control upper limit value, the safety control lower limit value and the safety control output value;

[0008] Collect the driving parameters of the vehicle in the driving state, match the driver's expected level with the actual level of the vehicle, and obtain the driver's expected coefficient;

[0009] The driving mode control output result is obtained by calculation based on the driver expectation coefficient, comfort control output value, comfort control upper limit value and safety control lower limit value.

[0010] In some implementations, calculating the current road adhesion coefficient and the road pass coefficient to obtain the safety control upper limit value, the safety control lower limit value, and the safety control output value includes:

[0011] Calculating a current road adhesion coefficient, and obtaining a first pedal map value and a first torque gradient value that match the road adhesion coefficient;

[0012] Collecting the current road speed limit and traffic flow to obtain a first coefficient, where the first coefficient includes a first pedal map coefficient and a first torque gradient coefficient;

[0013] multiplying the first pedal map value and the first torque gradient value by the first pedal map coefficient and the first torque gradient coefficient respectively to obtain a safety control pedal map upper limit value and a safety control torque gradient upper limit value;

[0014] Obtaining a second pedal map value and a second torque gradient value corresponding to a road adhesion coefficient of 0.2 as a safety control pedal map lower limit value and a safety control torque gradient lower limit value;

[0015] Obtaining a third pedal map value and a third torque gradient value corresponding to a road adhesion coefficient of 0.8 as a control initial value, wherein the control initial value includes a pedal map initial value and a torque gradient initial value;

[0016] The pedal map initial value and the torque gradient initial value are limited by the safety control pedal map upper limit value, the safety control torque gradient upper limit value, the safety control pedal map lower limit value and the safety control torque gradient lower limit value and then serve as the safety control pedal map output value and the safety control torque gradient output value.

[0017] In some implementations, the method for calculating the current road adhesion coefficient includes:

[0018] During the vehicle driving process, determining whether the number of times the traction control system (TCS) is triggered is greater than a preset first threshold within a preset time length, if so, determining that the driving force is greater than the adhesion force, if not, determining that the driving force is not greater than the adhesion force;

[0019] or,

[0020] Calculating the tire slip rate, determining whether the number of times the tire slip rate is greater than the second threshold value is greater than a third threshold value within a preset time length, if the number of times the tire slip rate is greater than the second threshold value is greater than the third threshold value, determining that the driving force is greater than the adhesion force, and if not, determining that the driving force is not greater than the adhesion force;

[0021] When the driving force is not greater than the adhesion force, the road adhesion coefficient is the preset default adhesion coefficient, which is 0.8;

[0022] When the driving force is greater than the adhesion force, the road adhesion coefficient is calculated using the following formula:

[0023]

[0024] Where μ is the road adhesion coefficient, T max is the maximum value of the output torque of the drive motor when the tire slip rate is greater than the second threshold or the maximum value of the output torque of the drive motor during the time period when the traction automatic control system is triggered, η is the transmission efficiency from the motor to the wheel end, i is the transmission ratio from the motor to the wheel end, r is the tire rolling radius, L is the vehicle wheelbase, b is the distance from the vehicle center of mass to the rear axle, g is the gravitational acceleration, G is the vehicle gravity, a is the vehicle acceleration, h g is the height of the vehicle's center of mass, and f(u,a) is a variable related to the vehicle speed and acceleration, which is used to compensate for calculation errors.

[0025] In some implementations, collecting the current road speed limit and traffic volume to obtain the first coefficient includes:

[0026] The current road speed limit and traffic volume are collected by an external camera, and the relationship between the current road speed limit and traffic volume and the preset road speed limit and traffic volume is determined;

[0027] If the current road speed limit is less than the preset road speed limit or the current road traffic volume is greater than the preset road traffic volume, the initial value of the pedal map coefficient and the initial value of the torque gradient coefficient are reduced to obtain a first pedal map coefficient and a first torque gradient coefficient;

[0028] If the current road speed limit is greater than the preset road speed limit or the current road traffic volume is less than the preset road traffic volume, the pedal map coefficient initial value and the torque gradient coefficient initial value are increased to obtain a first pedal map coefficient and a first torque gradient coefficient.

[0029] In some implementations, obtaining the current in-vehicle passenger information and obtaining the comfort control upper limit value and the comfort control output value by combining the safety control upper limit value and the safety control lower limit value includes:

[0030] Collect information about the current passengers in the car through the in-car camera and the sensors under the seats;

[0031] Obtaining a second coefficient according to the passenger information in the vehicle;

[0032] The second coefficient is multiplied by the upper limit of safety control to obtain the upper limit of comfort control;

[0033] The comfort control output value is obtained by taking the smaller of the safety control output value and the comfort control upper limit value and then taking the larger of the safety control lower limit value.

[0034] In some implementations, collecting the driving parameters of the vehicle in the driving state, matching the driver's expected level with the actual level of the vehicle, and obtaining the driver's expected coefficient includes:

[0035] Determine whether the vehicle is in a driving state, and if the vehicle is in a driving state, determine whether the dynamic adjustment triggering condition is currently met;

[0036] If the dynamic adjustment triggering conditions are met, the driver's accelerator pedal operation, the accelerator pedal opening and the vehicle speed corresponding to the accelerator pedal opening are collected, and the accelerator pedal opening change rate, vehicle acceleration and vehicle jerk are calculated;

[0037] According to the accelerator pedal opening and the corresponding vehicle speed, the driver's expected level of driving torque is obtained; according to the accelerator pedal opening rate and the corresponding vehicle speed, the driver's expected level of vehicle response speed is obtained; according to the vehicle acceleration and the corresponding vehicle speed, the level of actual vehicle driving torque is obtained; according to the vehicle jerk and the corresponding vehicle speed, the level of actual vehicle response speed is obtained;

[0038] The driver's expected level of driving torque and the level of actual driving torque of the vehicle, the driver's expected level of vehicle response speed and the level of actual vehicle response speed are compared respectively to obtain the driver's expected coefficient.

[0039] In some embodiments, respectively comparing the driver's expected level of driving torque with the level of the vehicle's actual driving torque, and the driver's expected level of vehicle response speed with the level of the vehicle's actual response speed, to obtain the driver's expected coefficient includes:

[0040] Comparing the driver's expected level of driving torque with the level of the actual driving torque of the vehicle, if the driver's expected level of driving torque is greater than the level of the actual driving torque of the vehicle, increasing the driver's expected pedal map coefficient; if the driver's expected level of driving torque is less than the level of the actual driving torque of the vehicle, reducing the driver's expected pedal map coefficient; if the driver's expected level of driving torque is equal to the level of the actual driving torque of the vehicle, the driver's expected pedal map coefficient is not changed;

[0041] Compare the driver's expected level of vehicle response speed with the level of the vehicle's actual response speed. If the driver's expected level of vehicle response speed is greater than the level of the vehicle's actual response speed, increase the driver's expected torque gradient coefficient; if the driver's expected level of vehicle response speed is less than the level of the vehicle's actual response speed, reduce the driver's expected torque gradient coefficient; if the driver's expected level of vehicle response speed is equal to the level of the vehicle's actual response speed, then the driver's expected torque gradient coefficient remains unchanged.

[0042] In some implementations, the driving mode control output result is obtained by calculation according to the driver expectation coefficient, the comfort control output value, the comfort control upper limit value and the safety control lower limit value, including:

[0043] After multiplying the driver expectation coefficient with the comfort control output value, the smaller of the comfort control upper limit value and the larger of the safety control lower limit value are obtained to obtain the driving mode control output result.

[0044] According to a second aspect of the present disclosure, an electric vehicle driving mode control device is provided, which is used to implement any of the above electric vehicle driving mode control methods, including:

[0045] The safety control output module is used to calculate the current road adhesion coefficient and road traffic coefficient, and obtain the safety control upper limit value, safety control lower limit value and safety control output value in combination with the control initial value;

[0046] The comfort control output module is used to obtain the current passenger information in the vehicle, and obtain the comfort control upper limit value and the comfort control output value by combining the safety control upper limit value, the safety control lower limit value and the safety control output value;

[0047] The driver expectation coefficient output module is used to collect the driving parameters of the vehicle in the driving state, match the driver's expectation level with the actual level of the vehicle, and obtain the driver's expectation coefficient;

[0048] The driving mode control output result calculation module is used to obtain the driving mode control output result after calculation based on the driver's expected coefficient, the comfort control output value, the comfort control upper limit value and the safety control lower limit value.

[0049] The electric vehicle driving mode control method and device provided by the present disclosure analyze and control the environmental conditions inside and outside the vehicle layer by layer, combine the analysis of the driver's driving behavior, take into account driving safety and riding comfort and meet the differentiated needs of the driver, realize real-time adjustment and automatic control of the driving mode, meet different driving needs in complex environments, reduce the frequency of the driver switching driving modes during driving, reduce driving intensity, allow the driver to focus on driving, and improve vehicle safety. BRIEF DESCRIPTION OF THE DRAWINGS

[0050] In order to more clearly illustrate the technical solutions of the embodiments of the present disclosure, the following briefly introduces the drawings required for use in the description of the embodiments. Obviously, the drawings described below are some embodiments of the present disclosure. For ordinary technicians in this field, other drawings can be obtained based on these drawings without creative work.

[0051] Figure 1The present invention is a flowchart of a method for controlling a driving mode of an electric vehicle provided by an embodiment of the present invention.

[0052] Figure 2 A structural block diagram of a driving mode control device for an electric vehicle provided in another embodiment of the present disclosure. DETAILED DESCRIPTION

[0053] In order to make the purpose, technical solution and advantages of the embodiments of the present disclosure clearer, the technical solution in the embodiments of the present disclosure will be clearly and completely described below in conjunction with the drawings in the embodiments of the present disclosure. Obviously, the described embodiments are part of the embodiments of the present disclosure, not all of the embodiments. Based on the embodiments in the present disclosure, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present disclosure.

[0054] Embodiment 1:

[0055] In this embodiment, refer to the attached manual Figure 1 , provides a method for controlling a driving mode of an electric vehicle, the method specifically comprising the following steps:

[0056] Step 1: Calculate the current road adhesion coefficient and road traffic coefficient, and combine them with the initial control value to obtain the safety control upper limit value, safety control lower limit value and safety control output value;

[0057] Step 2: Obtain the current passenger information in the vehicle, and obtain the comfort control upper limit value and the comfort control output value by combining the safety control upper limit value, the safety control lower limit value and the safety control output value;

[0058] Step 3: Collect the driving parameters of the vehicle in the driving state, match the driver's expected level with the actual level of the vehicle, and obtain the driver's expected coefficient;

[0059] Step 4: Calculate the driving mode control output result based on the driver expectation coefficient, comfort control output value, comfort control upper limit value and safety control lower limit value.

[0060] Specifically, the driving mode control output result may include a driving mode control output pedal map value and a driving mode control output torque gradient value. Thus, in the disclosed embodiment, each initial value, upper limit value, lower limit value and output value includes a pedal map value and a torque gradient value, and the road passability coefficient and the driver expectation coefficient include a pedal map coefficient and a torque gradient coefficient.

[0061] In an optional implementation manner, in step 1, calculating the current road adhesion coefficient and the road pass coefficient to obtain the safety control upper limit value, the safety control lower limit value and the safety control output value may include the following steps:

[0062] Step 1.1: Calculate the current road adhesion coefficient, and obtain the corresponding first pedal map value and first torque gradient value according to the road adhesion coefficient;

[0063] Step 1.2: Collect the current road speed limit value and traffic flow to obtain a first coefficient, where the first coefficient includes a first pedalmap coefficient and a first torque gradient coefficient;

[0064] Step 1.3: multiplying the first pedal map value and the first torque gradient value by the first pedal map coefficient and the first torque gradient coefficient respectively to obtain a safety control pedal map upper limit value and a safety control torque gradient upper limit value;

[0065] Step 1.4: Obtain the second pedal map value and the second torque gradient value corresponding to the road adhesion coefficient being equal to 0.2, as the safety control pedal map lower limit value and the safety control torque gradient lower limit value;

[0066] Step 1.5: Obtaining a third pedal map value and a third torque gradient value corresponding to a road adhesion coefficient of 0.8 as a control initial value, wherein the control initial value includes a pedal map initial value and a torque gradient initial value;

[0067] Step 1.6: The pedal map initial value and the torque gradient initial value are limited by the safety control pedal map upper limit value, the safety control torque gradient upper limit value, the safety control pedal map lower limit value and the safety control torque gradient lower limit value and serve as the safety control pedal map output value and the safety control torque gradient output value.

[0068] In an optional embodiment, in step 1.1, the method for calculating the current road adhesion coefficient includes:

[0069] During the vehicle driving process, it is judged whether the driving force is greater than the adhesion. The specific judgment method is to judge whether the number of times the traction control system (TCS) is triggered within a preset time length is greater than a preset first threshold value. If it is greater, it is judged that the driving force is greater than the adhesion force. If it is not greater, it is judged that the driving force is not greater than the adhesion force; or, calculate the tire slip rate, and judge whether the number of times the tire slip rate is greater than the second threshold value within the preset time length is greater than a third threshold value. If the number of times the tire slip rate is greater than the second threshold value is greater than the third threshold value, it is judged that the driving force is greater than the adhesion force. If it is not greater, it is judged that the driving force is not greater than the adhesion force. The values ​​of the preset time length, the first threshold value, the second threshold value and the third threshold value can be set by vehicle engineers according to different vehicle models.

[0070] When the driving force is not greater than the adhesion force, the road adhesion coefficient is the preset default adhesion coefficient, and the default adhesion coefficient is set to 0.8.

[0071] When the driving force is greater than the adhesion force, the road adhesion coefficient needs to be calculated. The calculation formula is as follows:

[0072]

[0073] Where μ is the road adhesion coefficient, T max is the maximum value of the output torque of the driving motor when the tire slip rate is greater than the second threshold or the maximum value of the driving motor torque during the time period when the traction automatic control system is triggered, η is the transmission efficiency from the motor to the wheel end, i is the transmission ratio from the motor to the wheel end, r is the tire rolling radius, L is the vehicle wheelbase, b is the distance from the vehicle center of mass to the rear axle, g is the gravitational acceleration, G is the vehicle gravity, a is the vehicle acceleration, and h g is the height of the vehicle's center of mass, and f(u,a) is a variable related to the vehicle speed and acceleration, which is used to compensate for calculation errors.

[0074] Specifically, when the driving force is greater than the adhesion force, the number of times that the tire slip rate is greater than the second threshold is greater than once, and the output torque of the driving motor corresponding to each moment when the tire slip rate is greater than the second threshold is collected, and the maximum value is taken as T max .

[0075] In an optional embodiment, in step 1.1, obtaining the first pedal map value and the first torque gradient value according to the road adhesion coefficient may include the following steps:

[0076] A table containing the mapping relationship between the road adhesion coefficient and the pedal map value and the torque gradient value is pre-set;

[0077] A table is looked up according to the road adhesion coefficient to obtain corresponding values ​​as the first pedal map value and the first torque gradient value.

[0078] Specifically, the mapping relationship between the road adhesion coefficient, the pedal map value, and the torque gradient value is determined by the following method:

[0079] The pedal map value and torque gradient value corresponding to different road adhesion coefficients are first calibrated through the accelerator pedal opening and vehicle speed. The calibrated torque gradient value is mapped to the road adhesion coefficient. The calibrated pedal map value and the driving torque converted to the wheel end by the vehicle electrical system are taken as the smaller one and mapped to the road adhesion coefficient.

[0080] In an optional embodiment, step 1.4 and step 1.5 are also performed by table lookup operations.

[0081] In an optional embodiment, if the road adhesion coefficient calculated in step 1.1 is less than the default adhesion coefficient, the vehicle driving state is monitored to see whether it satisfies the road adhesion coefficient recovery conditions. When the vehicle driving state satisfies the road adhesion coefficient recovery conditions, the current road adhesion coefficient is increased according to a preset ratio or fixed value. If the road adhesion coefficient recovery conditions are not met, no operation is performed.

[0082] The road adhesion coefficient recovery conditions include:

[0083] The driving torque is greater than the adhesion corresponding to the current road adhesion coefficient, but the tire slip rate does not exceed the second threshold or the automatic traction control system is not triggered.

[0084] or,

[0085] When the driving torque does not exceed the adhesion corresponding to the current road adhesion coefficient within a number of key cycles or a preset continuous time length.

[0086] Therefore, when the adhesion coefficient of the road on which the vehicle is traveling increases, that is, when the vehicle changes from a low-adhesion road surface to a high-adhesion road surface, it can respond more quickly to the change in road conditions, avoiding the situation where the road conditions have changed but the vehicle's driving torque cannot be increased because the road adhesion coefficient has not changed or has changed only slightly, further improving the degree of automation of driving mode control and meeting driving needs in complex road conditions.

[0087] Specifically, one key cycle is when an electric vehicle is powered on and off.

[0088] In an optional embodiment, when the vehicle driving state meets the road adhesion coefficient recovery condition, a fixed value can be added to the current road adhesion coefficient as a new road adhesion coefficient according to a certain step size and time interval until the current road adhesion coefficient is equal to the default adhesion coefficient.

[0089] In an optional embodiment, in step 1.2, collecting the current road speed limit value and traffic flow, and obtaining the first coefficient may include:

[0090] The current road speed limit and traffic volume are collected by an external camera, and the relationship between the current road speed limit and traffic volume and the preset road speed limit and traffic volume is determined;

[0091] If the current road speed limit is less than the preset road speed limit or the current road traffic volume is greater than the preset road traffic volume, the initial value of the pedal map coefficient and the initial value of the torque gradient coefficient are reduced to obtain a first pedal map coefficient and a first torque gradient coefficient;

[0092] If the current road speed limit is greater than the preset road speed limit or the current road traffic volume is less than the preset road traffic volume, the pedal map coefficient initial value and the torque gradient coefficient initial value are increased to obtain a first pedal map coefficient and a first torque gradient coefficient.

[0093] Specifically, the initial value of the pedal map coefficient and the initial value of the torque gradient coefficient are both 1.

[0094] In an optional embodiment, in step 1.6, taking the safety control pedal map output value as an example, the pedal map initial value is compared with the pedal map upper limit value and the pedal map lower limit value respectively; if the pedal map initial value does not exceed the range limited by the safety control pedal map upper limit value and the safety control pedal map lower limit value, then the pedal map initial value is the safety control pedal map output value; if the pedal map initial value is greater than the safety control pedal map upper limit value, then the safety control pedal map upper limit value is taken as the safety control pedal map output value; if the pedal map initial value is less than the safety control pedal map lower limit value, then the safety control pedal map lower limit value is taken as the safety control pedal map output value.

[0095] In an optional embodiment, in step 2, obtaining the current in-vehicle passenger information, combining the safety control upper limit value, the safety control lower limit value and the safety control output value, and obtaining the comfort control upper limit value and the comfort control output value include:

[0096] Collect information about the current passengers in the car through the in-car camera and the sensors under the seats;

[0097] Obtaining a second coefficient according to the passenger information in the vehicle;

[0098] The second coefficient is multiplied by the upper limit of safety control to obtain the upper limit of comfort control;

[0099] The comfort control output value is obtained by taking the smaller of the safety control output value and the comfort control upper limit value and then taking the larger of the safety control lower limit value.

[0100] Specifically, obtaining the second coefficient according to the passenger information in the vehicle specifically includes:

[0101] When there are passengers in the car and the passengers are elderly or children, the second coefficient ranges from 0.2 to 0.5;

[0102] When there are passengers in the car and the passengers are not elderly or children, the second coefficient ranges from 0.6 to 0.9;

[0103] When there are no passengers in the car, the second coefficient takes the value of 1.

[0104] The above only provides a value range for the second coefficient. According to the number of passengers in the car and the number of elderly people or children in the car, the vehicle engineer can set the value of the second coefficient according to the specific model.

[0105] In an optional embodiment, in step 3, the driving parameters of the vehicle in the driving state are collected, the driver's expected level is matched with the actual level of the vehicle, and the driver's expected coefficient is obtained, including:

[0106] Step 3.1: Determine whether the vehicle is in a driving state. If the vehicle is in a driving state, determine whether the dynamic adjustment triggering condition is currently met;

[0107] Step 3.2: If the dynamic adjustment triggering condition is met, collect the accelerator pedal opening and the vehicle speed corresponding to the accelerator pedal opening, and calculate the accelerator pedal opening change rate, vehicle acceleration, and vehicle jerk;

[0108] Step 3.3: According to the accelerator pedal opening and the corresponding vehicle speed, the driver's expected level of driving torque is obtained; according to the accelerator pedal opening rate and the corresponding vehicle speed, the driver's expected level of vehicle response speed is obtained; according to the vehicle acceleration and the corresponding vehicle speed, the level of the vehicle's actual driving torque is obtained; according to the vehicle's jerk and the corresponding vehicle speed, the level of the vehicle's actual response speed is obtained;

[0109] Step 3.4: Compare the driver's expected level of driving torque with the level of the vehicle's actual driving torque, the driver's expected level of vehicle response speed with the level of the vehicle's actual response speed, and obtain the driver's expected coefficient.

[0110] Specifically, in step 3.1, determining whether the vehicle is in a driving state can be achieved by the following steps:

[0111] During vehicle driving, the driving torque output signal, accelerator pedal opening, gear position and vehicle speed are obtained;

[0112] When the current gear is the driving gear, the accelerator pedal opening is reduced, and the motor has driving torque output, it is determined that the vehicle is in a driving state.

[0113] Specifically, in step 3.1, determining whether the dynamic adjustment triggering condition is currently met may include:

[0114] Get the current steering wheel angle and road slope,

[0115] When the current steering wheel angle is less than the fourth threshold and the road slope is less than the fifth threshold, it is determined that the dynamic adjustment trigger condition is met.

[0116] The road slope can be obtained by a slope sensor provided in the vehicle.

[0117] In an optional embodiment, in step 3.3, obtaining the driver's expected level of driving torque according to the accelerator pedal opening and the corresponding vehicle speed specifically includes:

[0118] The driver's expected driving torque level is divided into five levels: very large, large, medium, small, and very small according to the size of the accelerator pedal opening and the vehicle speed;

[0119] The driver's expected level of driving torque is obtained according to the current accelerator pedal opening and the corresponding vehicle speed.

[0120] Specifically, at the same vehicle speed, a larger accelerator pedal opening indicates that the driver has a greater expectation for the driving torque, and at the same accelerator pedal opening, a higher vehicle speed indicates that the driver has a greater expectation for the driving torque.

[0121] In an optional embodiment, in step 3.3, obtaining the driver's expected level of vehicle response speed according to the accelerator pedal opening change rate and the corresponding vehicle speed specifically includes:

[0122] The driver's expectations of vehicle response speed are divided into five levels: very fast, relatively fast, medium, relatively slow, and very slow according to the change rate of the accelerator pedal opening and the vehicle speed.

[0123] The driver's expected level of vehicle response speed is obtained based on the current accelerator pedal opening change rate and the corresponding vehicle speed.

[0124] Specifically, at the same vehicle speed, a faster accelerator pedal opening change rate indicates that the driver's expectation for the vehicle's response speed is faster, and at the same accelerator pedal opening change rate, a higher vehicle speed indicates that the driver's expectation for the vehicle's response speed is faster.

[0125] In an optional embodiment, in step 3.3, obtaining the level of the actual driving torque of the vehicle according to the vehicle acceleration and the corresponding vehicle speed specifically includes:

[0126] According to the acceleration and corresponding speed of the vehicle, the actual driving torque of the vehicle is divided into five levels: large, large, medium, small and very small.

[0127] According to the current vehicle acceleration and the corresponding vehicle speed, the level of the vehicle's actual driving torque is obtained.

[0128] Specifically, at the same vehicle speed, a greater vehicle acceleration indicates a greater actual vehicle driving torque, and at the same vehicle acceleration, a higher vehicle speed indicates a greater actual vehicle driving torque.

[0129] In an optional embodiment, in step 3.3, obtaining the level of the actual response speed of the vehicle according to the jerk of the vehicle and the corresponding vehicle speed specifically includes:

[0130] The actual response speed of the vehicle is divided into five levels: fast, fast, medium, slow, and very slow according to the jerkiness and corresponding speed of the vehicle in advance;

[0131] According to the current vehicle jerkiness and corresponding vehicle speed, the level of the vehicle's actual response speed is obtained.

[0132] Specifically, at the same vehicle speed, a greater vehicle jerk indicates a faster actual vehicle response, and at the same vehicle jerk, a higher vehicle speed indicates a faster actual vehicle response.

[0133] In an optional embodiment, in step 3.4, the driver's expected level of driving torque is compared with the level of the actual driving torque of the vehicle, and the driver's expected level of vehicle response speed is compared with the level of the actual response speed of the vehicle, and the driver's expected coefficient is obtained by:

[0134] Comparing the driver's expected level of driving torque with the level of the actual driving torque of the vehicle, if the driver's expected level of driving torque is greater than the level of the actual driving torque of the vehicle, increasing the driver's expected pedal map coefficient; if the driver's expected level of driving torque is less than the level of the actual driving torque of the vehicle, reducing the driver's expected pedal map coefficient; if the driver's expected level of driving torque is equal to the level of the actual driving torque of the vehicle, the driver's expected pedal map coefficient is not changed;

[0135] Compare the driver's expected level of vehicle response speed with the level of the vehicle's actual response speed. If the driver's expected level of vehicle response speed is greater than the level of the vehicle's actual response speed, increase the driver's expected torque gradient coefficient; if the driver's expected level of vehicle response speed is less than the level of the vehicle's actual response speed, reduce the driver's expected torque gradient coefficient; if the driver's expected level of vehicle response speed is equal to the level of the vehicle's actual response speed, then the driver's expected torque gradient coefficient remains unchanged.

[0136] Specifically, the driver's expected pedal map coefficient and the driver's expected torque gradient coefficient are both 1. When the driver's expected level is greater than the vehicle's actual level, the driver's expected pedal map coefficient and the driver's expected torque gradient coefficient are increased to be greater than 1. When the driver's expected level is less than the vehicle's actual level, the driver's expected pedal map coefficient and the driver's expected torque gradient coefficient are reduced to be less than 1.

[0137] Specifically, when the driver's expected level is greater than the vehicle's actual level, the greater the gap between the driver's expected level and the vehicle's actual level, the greater the increase in the driver's expected pedal map coefficient and the driver's expected torque gradient coefficient; when the driver's expected level is lower than the vehicle's actual level, the greater the gap between the driver's expected level and the vehicle's actual level, the smaller the change in the driver's expected pedal map coefficient and the driver's expected torque gradient coefficient.

[0138] In an optional embodiment, in step 4, the driving mode control output result obtained by calculation according to the driver expectation coefficient, the comfort control output value, the comfort control upper limit value and the safety control lower limit value includes:

[0139] After multiplying the driver expectation coefficient with the comfort control output value, the smaller of the comfort control upper limit value and the larger of the safety control lower limit value are obtained to obtain the driving mode control output result.

[0140] The electric vehicle driving mode control method provided by the present invention analyzes and controls the environmental conditions inside and outside the vehicle layer by layer, combines the analysis of the driver's driving behavior, takes into account driving safety, riding comfort and meets the differentiated needs of the driver, realizes real-time adjustment and automatic control of the driving mode, meets different driving needs in complex environments, reduces the frequency of the driver switching driving modes during driving, reduces driving intensity, allows the driver to focus on driving, and improves vehicle safety.

[0141] Embodiment 2:

[0142] In this embodiment, refer to the attached manual Figure 2 , provides an electric vehicle driving mode control device, which is used to implement any electric vehicle driving mode control method in the above method embodiments, including:

[0143] The safety control output module 101 is used to calculate the current road adhesion coefficient and road pass coefficient, and obtain the safety control upper limit value, the safety control lower limit value and the safety control output value in combination with the control initial value;

[0144] The comfort control output module 102 is used to obtain the current passenger information in the vehicle, and obtain the comfort control upper limit value and the comfort control output value by combining the safety control upper limit value, the safety control lower limit value and the safety control output value;

[0145] The driver expectation coefficient output module 103 is used to collect the driving parameters of the vehicle in the driving state, match the driver's expectation level with the actual level of the vehicle, and obtain the driver's expectation coefficient;

[0146] The driving mode control output result calculation module 104 is used to obtain the driving mode control output result through calculation according to the driver expectation coefficient, the comfort control output value, the comfort control upper limit value and the safety control lower limit value.

[0147] The electric vehicle driving mode control method provided by the present invention analyzes and controls the environmental conditions inside and outside the vehicle layer by layer, combines the analysis of the driver's driving behavior, takes into account driving safety, riding comfort and meets the differentiated needs of the driver, realizes real-time adjustment and automatic control of the driving mode, meets different driving needs in complex environments, reduces the frequency of the driver switching driving modes during driving, reduces driving intensity, allows the driver to focus on driving, and improves vehicle safety.

[0148] The above sequence of the embodiments of this specification is for description only and does not represent the advantages and disadvantages of the embodiments. And the above describes specific embodiments of the specification. Other embodiments are within the scope of the appended claims. In some cases, the actions or steps recorded in the claims can be performed in an order different from that in the embodiments and still achieve the desired results. In addition, the processes depicted in the drawings do not necessarily require the specific order or continuous order shown to achieve the desired results. In some embodiments, multitasking and parallel processing are also possible or may be advantageous.

[0149] Each embodiment in this specification is described in a progressive manner, and the same or similar parts between the embodiments can be referred to each other, and each embodiment focuses on the differences from other embodiments. In particular, for the device embodiment, since it is basically similar to the method embodiment, the description is relatively simple, and the relevant parts can be referred to the partial description of the method embodiment.

[0150] A person skilled in the art will understand that all or part of the steps to implement the above embodiments may be accomplished by hardware or by instructing related hardware through a program, and the program may be stored in a computer-readable storage medium, and the above-mentioned storage medium may be a read-only memory, a disk or an optical disk, etc.

[0151] The above are only preferred embodiments of the present disclosure and are not intended to limit the present disclosure. Any modifications, equivalent substitutions, improvements, etc. made within the spirit and principles of the present disclosure should be included in the protection scope of the present disclosure.

Claims

1. A method for controlling an electric vehicle driving mode, characterized in that: include: Calculate the current road adhesion coefficient and road traffic coefficient, and combine them with the initial control value to obtain the safety control upper limit value, safety control lower limit value and safety control output value; Obtain the current passenger information in the vehicle, and obtain the comfort control upper limit value and the comfort control output value by combining the safety control upper limit value, the safety control lower limit value and the safety control output value; Collect the driving parameters of the vehicle in the driving state, match the driver's expected level with the actual level of the vehicle, and obtain the driver's expected coefficient; The driving mode control output result is obtained by calculation according to the driver expectation coefficient, the comfort control output value, the comfort control upper limit value and the safety control lower limit value; The calculating of the current road adhesion coefficient and the road pass coefficient to obtain the safety control upper limit value, the safety control lower limit value and the safety control output value includes: Calculating a current road adhesion coefficient, and obtaining a corresponding first pedal map value and a first torque gradient value according to the road adhesion coefficient; Collecting the current road speed limit and traffic flow to obtain a first coefficient, where the first coefficient includes a first pedal map coefficient and a first torque gradient coefficient; multiplying the first pedal map value and the first torque gradient value by the first pedal map coefficient and the first torque gradient coefficient respectively to obtain a safety control pedal map upper limit value and a safety control torque gradient upper limit value; Obtaining a second pedal map value and a second torque gradient value corresponding to a road adhesion coefficient of 0.2 as a safety control pedal map lower limit value and a safety control torque gradient lower limit value; Obtaining a third pedal map value and a third torque gradient value corresponding to a road adhesion coefficient of 0.8 as a control initial value, wherein the control initial value includes a pedal map initial value and a torque gradient initial value; The pedal map initial value and the torque gradient initial value are limited by the safety control pedal map upper limit value, the safety control torque gradient upper limit value, the safety control pedal map lower limit value and the safety control torque gradient lower limit value and serve as the safety control pedal map output value and the safety control torque gradient output value; Obtain the current passenger information in the car, and combine the safety control upper limit and safety control lower limit to obtain the comfort control upper limit and comfort control output value, including: Collect information about the current passengers in the car through the in-car camera and the sensors under the seats; Obtaining a second coefficient according to the passenger information in the vehicle; The second coefficient is multiplied by the upper limit of safety control to obtain the upper limit of comfort control; The smaller of the safety control output value and the comfort control upper limit value is taken, and the larger of the safety control lower limit value is taken to obtain the comfort control output value; The driving mode control output results obtained after calculation based on the driver expectation coefficient, comfort control output value, comfort control upper limit value and safety control lower limit value include: After multiplying the driver expectation coefficient with the comfort control output value, the smaller of the comfort control upper limit value and the larger of the safety control lower limit value are obtained to obtain the driving mode control output result.

2. The electric vehicle driving mode control method according to claim 1, characterized in that: Methods for calculating the current road adhesion coefficient include: During the vehicle driving process, determining whether the number of times the traction control system (TCS) is triggered is greater than a preset first threshold within a preset time length, if so, determining that the driving force is greater than the adhesion force, and if not, determining that the driving force is not greater than the adhesion force; or, Calculating the tire slip rate, determining whether the number of times the tire slip rate is greater than the second threshold value is greater than a third threshold value within a preset time length, if the number of times the tire slip rate is greater than the second threshold value is greater than the third threshold value, determining that the driving force is greater than the adhesion force, and if not, determining that the driving force is not greater than the adhesion force; When the driving force is not greater than the adhesion force, the road adhesion coefficient is the preset default adhesion coefficient, which is 0.8; When the driving force is greater than the adhesion force, the road adhesion coefficient is calculated using the following formula: Where μ is the road adhesion coefficient, T max is the maximum value of the output torque of the drive motor when the tire slip rate is greater than the second threshold or the maximum value of the output torque of the drive motor during the time period when the traction automatic control system is triggered, η is the transmission efficiency from the motor to the wheel end, i is the transmission ratio from the motor to the wheel end, r is the tire rolling radius, L is the vehicle wheelbase, b is the distance from the vehicle center of mass to the rear axle, g is the gravitational acceleration, G is the vehicle gravity, a is the vehicle acceleration, h g is the height of the vehicle's center of mass, and f(u,a) is a variable related to the vehicle speed and acceleration, which is used to compensate for calculation errors.

3. The electric vehicle driving mode control method according to claim 2, characterized in that: Collect the current road speed limit and traffic volume to obtain the first coefficient including: The current road speed limit and traffic volume are collected by an external camera, and the relationship between the current road speed limit and traffic volume and the preset road speed limit and traffic volume is determined; If the current road speed limit is less than the preset road speed limit or the current road traffic volume is greater than the preset road traffic volume, the initial value of the pedal map coefficient and the initial value of the torque gradient coefficient are reduced to obtain a first pedal map coefficient and a first torque gradient coefficient; If the current road speed limit is greater than the preset road speed limit or the current road traffic volume is less than the preset road traffic volume, the pedal map coefficient initial value and the torque gradient coefficient initial value are increased to obtain a first pedal map coefficient and a first torque gradient coefficient.

4. The electric vehicle driving mode control method according to claim 1, characterized in that: Collect the driving parameters of the vehicle in the driving state, match the driver's expected level with the actual level of the vehicle, and obtain the driver's expected coefficient including: Determine whether the vehicle is in a driving state, and if the vehicle is in a driving state, determine whether the dynamic adjustment triggering condition is currently met; If the dynamic adjustment triggering conditions are met, the driver's accelerator pedal operation, the accelerator pedal opening and the vehicle speed corresponding to the accelerator pedal opening are collected, and the accelerator pedal opening change rate, vehicle acceleration and vehicle jerk are calculated; According to the accelerator pedal opening and the corresponding vehicle speed, the driver's expected level of driving torque is obtained; according to the accelerator pedal opening rate and the corresponding vehicle speed, the driver's expected level of vehicle response speed is obtained; according to the vehicle acceleration and the corresponding vehicle speed, the level of actual vehicle driving torque is obtained; according to the vehicle jerk and the corresponding vehicle speed, the level of actual vehicle response speed is obtained; The driver's expected level of driving torque and the level of actual driving torque of the vehicle, the driver's expected level of vehicle response speed and the level of actual vehicle response speed are compared respectively to obtain the driver's expected coefficient.

5. The electric vehicle driving mode control method according to claim 4, characterized in that: The driver's expectation level of driving torque and the level of actual driving torque of the vehicle, the driver's expectation level of vehicle response speed and the level of actual vehicle response speed are compared respectively, and the driver's expectation coefficient is obtained, including: Comparing the driver's expected level of driving torque with the level of the actual driving torque of the vehicle, if the driver's expected level of driving torque is greater than the level of the actual driving torque of the vehicle, increasing the driver's expected pedal map coefficient; if the driver's expected level of driving torque is less than the level of the actual driving torque of the vehicle, reducing the driver's expected pedal map coefficient; if the driver's expected level of driving torque is equal to the level of the actual driving torque of the vehicle, the driver's expected pedal map coefficient is not changed; Compare the driver's expected level of vehicle response speed with the level of the vehicle's actual response speed. If the driver's expected level of vehicle response speed is greater than the level of the vehicle's actual response speed, increase the driver's expected torque gradient coefficient; if the driver's expected level of vehicle response speed is less than the level of the vehicle's actual response speed, reduce the driver's expected torque gradient coefficient; if the driver's expected level of vehicle response speed is equal to the level of the vehicle's actual response speed, then the driver's expected torque gradient coefficient remains unchanged.

6. An electric vehicle driving mode control device, used to implement the electric vehicle driving mode control method according to any one of claims 1 to 5, characterized in that: include: The safety control output module is used to calculate the current road adhesion coefficient and road traffic coefficient, and combine the control initial value to obtain the safety control upper limit value, safety control lower limit value and safety control output value; The comfort control output module is used to obtain the current passenger information in the vehicle, and obtain the comfort control upper limit value and the comfort control output value by combining the safety control upper limit value, the safety control lower limit value and the safety control output value; The driver expectation coefficient output module is used to collect the driving parameters of the vehicle in the driving state, match the driver's expectation level with the actual level of the vehicle, and obtain the driver's expectation coefficient; The driving mode control output result calculation module is used to obtain the driving mode control output result after calculation based on the driver's expected coefficient, the comfort control output value, the comfort control upper limit value and the safety control lower limit value.

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